JPH08189338A - Diesel exhaust gas filter manufacturing method - Google Patents

Abstract

(57) [Abstract] [Purpose] Diesel exhaust gas filter manufacturing that does not leak soot from the plugged part, can be manufactured efficiently, and does not cause uneven amount of plugging material filled in each cell. The purpose is to provide a method. A molding step of extruding a two-layer cell honeycomb structure molded body 1 and a press-fitting hole 2 formed in an end portion of an outer peripheral surface 3 of the molded body on the plugging cell of the two-layer cells. An installation step, a plugging step in which a plugging material is press-fitted through the press-fitting holes 2 to seal the cells to be plugged, and a material of the same quality as that of the two-layer cell honeycomb structure molded body 1 is formed on the outer peripheral surface 3 of the molded body. There is an integration step of applying a paste and laminating, press-bonding, and firing a predetermined number of two-layer cell honeycomb structure molded bodies 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a diesel exhaust gas filter for collecting particulate matter (hereinafter referred to as "soot") contained in exhaust gas discharged from a combustion engine such as a diesel engine. , In particular, soot is collected as exhaust gas passes through the cell wall in the filter, and the collected soot is burned and regenerated by a heat source such as an electric heater or a burner to regenerate (clean) the filter. The present invention relates to a method for manufacturing a diesel exhaust gas filter that protects the global environment by filtering harmful substances such as soot discharged into the atmosphere.

[0002]

2. Description of the Related Art The following is proposed as a diesel exhaust gas filter for collecting soot discharged from a diesel engine.

That is, a metal wire mesh coated with a heat-resistant ceramic material such as alumina oxide to form a filter structure or a mesh structure formed of an organic polymer material is impregnated in a ceramic slurry solution to form a filter. Structured ceramic foam filter, fibrous honeycomb ceramic filter with high soot collection efficiency, which is obtained by dispersing and agglomerating inorganic fibers with ceramic powder to produce a sheet of ceramic paper, and then performing molding by the corrugated molding method and firing. For example, a ceramic honeycomb filter having a honeycomb shape in which a cordierite raw material is molded by an extrusion molding machine and fired to have a porous structure.

These diesel exhaust gas filters are
It was mounted on a heat-resistant container and installed in the exhaust manifold of a diesel engine to collect the soot discharged from the engine, and after a certain period of time, burned it with a heat source such as an electric heater or a burner to clean the filter. Later, we repeatedly collected and regenerated diesel exhaust gas,
It prevents the emission of pollutants in the exhaust gas from the engine to the atmosphere.

As a plugging method of the diesel exhaust gas filter as described above, there is a method described in JP-B-63-24731 or JP-A-5-184833.

Japanese Patent Publication No. 63-24731 discloses a method for plugging a specific cell having a honeycomb structure consisting of a large number of cells into a specific sealing film on a sealing film made of paper or synthetic resin. Create a film with holes to introduce a stopper, and affix this film to the end face of the filter that is plugged, and then introduce the plugging material under pressure through a piston or the like through this film. , A method of introducing a plugging material into a specific cell and sealing it.

Further, in Japanese Patent Laid-Open No. 184833/1993, a sealing having an opening is formed so that the end face of the honeycomb structure to be sealed faces downward and the sealing material can be selectively injected into the upper end face. Place the material container, put the sealing material in the container, give vibration to the sealing material container, by this vibration the sealing material falls through the through-hole of the honeycomb structure to form a dense layer on the lower end surface. A method of forming and sealing any cells of a honeycomb structure is described.

[0008]

However, the above-mentioned conventional diesel exhaust gas filter has a problem at the time of collecting the exhaust gas by the filter, because the plugging material is not sufficiently filled in the cell, especially when collecting the exhaust gas. There was a problem that soot leaked from the plugged portion for stopping the soot, and the intention to collect the soot in the exhaust gas was scattered into the atmosphere.

Further, the method of sticking the above-mentioned sealing film to seal the cell has the following problems. That is, when sticking the extruded honeycomb structure and the sealing film provided with the passage holes to the end surface portion of the filter, the surfaces of the filter must be uniformly parallel, and if the surface is rough, When the sealing material is introduced, the sealing material is introduced outside the cell to be sealed, or when the sealing material is introduced under pressure, the film is deformed and the sealing material is attached to other cells. There was a problem. In addition, since this sealing film is burned, burned, and burned off while it is attached to the filter, unnecessary cost is required in the production of the sealing film, and it is not easy to use the film when it is attached to the end face of the filter. It requires a lot of labor, time, and cost to correct the part where these plugging materials are attached to other cells, attach the film, etc., and the diesel exhaust gas filter cannot be efficiently manufactured. There was a problem. Furthermore, in the sealing method in which the sealing material container with the sealing material is placed on the upper end surface of the honeycomb structure and is vibrated to drop and fill the lower end surface of the honeycomb structure, The amount of plugging material filled in each cell may be such that the encapsulating material inside may drop due to vibration, or the plugging material may cause a bridge phenomenon such as clogging. There is a problem in that combustion becomes nonuniform because the amount of soot in the exhaust gas accumulated in each cell changes due to the nonuniformity.

The present invention solves the above-mentioned conventional problems, soot can be efficiently produced without leakage of soot from the plugging portion, and the amount of plugging material filled in each cell is uneven. An object of the present invention is to provide a method for manufacturing a diesel exhaust gas filter that does not meet the requirements.

[0011]

In order to achieve this object, a method for manufacturing a diesel exhaust gas filter according to claim 1 of the present invention comprises a molding step of extruding a two-layer cell honeycomb structure molded body and a two-layer structure. A punching step of punching a press-fitting hole at an end portion of a molded body outer peripheral surface on a cell to be plugged of cells, and a sealing step of sealing a cell to be plugged by press-fitting a plugging material from the press-fitting hole. And an integration step of applying a paste of the same material as that of the formed body to the outer peripheral surface of the formed body and integrating a predetermined number of two-layer cell honeycomb structure formed bodies by stacking, pressure bonding and firing. Have

According to a second aspect of the present invention, there is provided a method of producing a diesel exhaust gas, wherein a forming step of extruding a two-layer cell honeycomb structure formed body and an end portion of an outer peripheral surface of the formed body on a plugging cell of the two-layer cells. A step of forming a notch in the groove, a step of injecting a plugging material into the notch and sealing the cell for plugging, and a paste of the same material as the molded body on the outer peripheral surface of the molded body. It has a constitution including an integration step of integrating a predetermined number of two-layer cell honeycomb structure molded bodies by applying and stacking, pressure bonding and firing.

Here, the two-layer cell honeycomb structure molded body is
It is formed of aluminum titanate, silica, cordierite, or mullite. This is heat resistant,
This is because it has excellent moldability.

[0014]

With the above structure, the plugging material can be surely press-fitted or injected into each cell that needs to be plugged through the press-fitting hole or notch, so that exhaust gas discharged from a diesel engine or the like is not leaked. It can be reliably collected. This prevents the release of harmful pollutants into the atmosphere.

Further, the diesel exhaust gas filter manufactured with the above-mentioned structure is an integral type, has no soot leakage due to vibration during mounting, etc., and has strength practically no problem.

Further, since a series of manufacturing steps are simple operations such as forming punching / cutting of press-fitting holes, press-fitting / injecting plugging material, applying paste to a molded body, laminating / press-bonding / firing. Robot work can be performed and work efficiency can be improved.

Furthermore, since it is possible to visually or visually judge that the plugging material has been securely press-fitted or injected, it is possible to adjust the amount of the plugging material filled in each cell so as not to be non-uniform. Therefore, the combustion in each cell can be made uniform.

[0018]

【Example】

(Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing a diesel exhaust gas filter according to an embodiment of the present invention, and FIG. 2 is an enlarged view of part A of FIG. In FIGS. 1 and 2, 1 is a two-layer cell honeycomb structure formed body, 2 is a press-fitting hole for press-fitting a plugging material, 3 is an outer peripheral surface of the two-layer cell honeycomb structure formed body, 4 is an exhaust gas inlet side, 5 is the exhaust gas outlet side.

First, a method of forming the two-layer cell honeycomb structure formed body 1 will be described. Bonded to 100% by weight of the raw material synthetic aluminum titanate with an average particle size of 5 μm (the manuscript has 100 parts, but since the description of each component that follows it is% by weight, it was set to% by weight) 20% by weight of methyl cellulose as a material, 4% by weight of glycerin as a lubricant, 10% by weight of stearic acid emulsion as a release agent, 50% by weight of combustible materials, and 30% by weight of water in a mixer. And mixed, and then sufficiently kneaded with a vacuum kneader to eliminate air traps inside.
Then, the kneaded product was aged for one day to make the water content of the kneaded product uniform, and the mixture was extruded into a predetermined shape with a vacuum extrusion molding machine to obtain a two-layer cell honeycomb structure formed body 1 of FIG. (At this point, the press-fitting hole 2 has not been formed yet). Two
The layer cell honeycomb structure formed body 1 has a shape of width 125 mm × thickness 6.8 mm × length 150 mm, and the number of cells is 100.
It has a two-layer cell shape of cell / inch ² .

Next, by means of an automatic perforator, press-fitting holes 2 for press-fitting the plugging material into specific cells of the extruded two-layer cell honeycomb structure formed body 1 are provided at the exhaust gas inlet side 4 and the outlet side. Alternate on side 5 (if the inlet side of the same cell is open, the outlet side is plugged; if the inlet side of the same cell is plugged, the outlet side is open ), And also the upper and lower cells were alternated. After a certain amount of a plugging material having a viscosity of 20 to 50 poise, which was made by using a binder, water, and a thickening agent, the same material as that used in extrusion molding, was pressed into the press-fitting hole 2, and then the plugging material was dried. .

Next, the plugging material was similarly press-fitted through the press-fitting holes 2 on the back surface side of the press-fitted surface to plug specific cells. Then, a paste material made of the same material as the two-layer cell honeycomb structure molded body 1 was applied to the outer peripheral surface 3 of the two-layer cell honeycomb structure molded body 1 by a roller transfer method. The two-layer cell honeycomb structure molded body 1 obtained in the same manner was laminated and pressure-bonded to the outer peripheral surface 3 coated with the paste by the above roller transfer method. FIG. 3 is a perspective view showing a laminated body of the diesel exhaust gas filter of FIG.
In FIG. 3, 1 is a two-layer cell honeycomb structure molded body, 2 is a press-fitting hole, 3 is an outer peripheral surface, 4 is an exhaust gas inlet side, 5 is an exhaust gas outlet side, and these are the same as those in FIG. The same reference numerals are given and the description is omitted.

The above-mentioned pressure bonding is 0.02 kg / cm ^{2 to} 0.
A pressure of 06 kg / cm ² was applied. When the pressure for pressure bonding was 0.01 kg / cm ² or less, there was a problem that the laminate was peeled off after firing. Further, when the pressure of the pressure bonding is 0.1 kg / cm ² or more, the cell portion of the two-layer cell honeycomb structure molded body 1 is deformed.

Next, as described above, the layers are laminated in a predetermined shape.
For the pressure-bonded laminate of FIG. 3, a firing temperature of 1450
Firing was performed under the condition of 4 ° C. for 4 hours to obtain a diesel exhaust gas filter made of aluminum titanate.

The diesel exhaust gas filter thus obtained was attached to the exhaust pipe of a 3400 cc diesel engine, and a combustor having an electric heater for ignition incorporated in a case was attached so that the collected soot could be regenerated by combustion. Engine speed 1200 rpm, torque 20 kg
The engine was operated under the condition of m and the particulate matter such as soot in the exhaust gas discharged from the diesel engine was collected.

In order to evaluate the collection, the smoke value of the soot discharged from the engine, the smoke value after filtering with a filter, and the leakage of the cell portion visually
I checked the traces. The results are shown in (Table 1).

[0027]

[Table 1]

After that, the adhered fine particles of soot and the like were burned and regenerated by an electric heater and the same evaluation as above was carried out, and the same result was obtained.

As is clear from (Table 1), according to the present embodiment, there is no leakage of fine particle components such as soot from the plugged cells, and the soot can be collected in a stable manner. Can be obtained. Although not specified in this example, a diesel exhaust gas filter was obtained by applying the same manufacturing method to ceramics such as silica, cordierite, and mullite, but the same as in (Table 1). I was able to get the result.

As described above, according to this embodiment, the press-fitting hole 2
Since the plugging material can be surely press-fitted into each cell that requires plugging through, the exhaust gas discharged from the diesel engine or the like can be reliably collected without leaking.
Further, the diesel exhaust gas filter manufactured in this embodiment is of an integral type, has no soot leakage due to vibration during mounting, etc., and has a strength that poses no practical problem. Further, the series of manufacturing steps is performed by the press-fitting hole 2
Since it is a simple work of piercing, press-fitting the plugging material, applying paste to the two-layer cell honeycomb structure molded body 1, laminating, pressure bonding, and firing, robot work can be performed and work efficiency can be improved. it can. Further, since it can be judged visually or visually that the plugging material has been securely press-fitted, the amount of the plugging material filled in each cell can be adjusted so as not to be uneven.

(Embodiment 2) FIG. 4 is a perspective view showing a diesel exhaust gas filter according to another embodiment of the present invention, and FIG. 5 is an enlarged view of portion B in FIG. 4 and 5, 6 is 2
A layer cell honeycomb structure molded body, 7 is a notch for injecting a plugging material, 8 is an outer peripheral surface of the two layer cell honeycomb structure molded body 6, 9
Is an exhaust gas inlet side, and 10 is an exhaust gas outlet side.

First, the method for forming the two-layer cell honeycomb structure formed body 6 will be described. Aluminum component is 10% by weight,
Raw materials consisting of 85% by weight of silica component and 5% by weight of potassium titanate component were weighed, wet-mixed in a ball mill for 48 hours, and then dried in a drier. Thereafter, this mixed raw material was pulverized with a kneader, and to 100% by weight of this mixture, 20% by weight of methyl cellulose as a binder, 5% by weight of glycerin as a lubricant, and a stearic acid emulsion as a release agent. 12% by weight, combustible combustibles 65% by weight, and water 35% by weight were thoroughly mixed with a mixer. After that, kneading was performed with a vacuum kneader in order to eliminate air accumulation inside. Then, the kneaded product is aged for one day to make the water content of the kneaded product uniform, and the mixture is extruded into a predetermined shape by a vacuum extrusion molding machine.
Thus, the two-layer cell honeycomb structure molded body 6 was obtained (the notches 7 are not formed yet at this point). The two-layer cell honeycomb structure molded body 6 has a shape of width 125 mm × thickness 6.8 mm × length 150 mm, and the number of cells is 100 cells / inch ^2.
Is a two-layer cell shape.

Next, a notch 7 for injecting a plugging material into a specific cell of the extruded two-layer cell honeycomb structure formed body 6 is formed by a rotary cutter machine, and an exhaust gas inlet side 9 and an outlet side 10 are formed. Alternately (when the inlet side of the same cell is open, the outlet side is plugged, and when the inlet side of the same cell is plugged, the outlet side is opened). Also, the upper and lower cells were formed alternately. After a certain amount of a plugging material having a viscosity of 20 to 50 poise, which was made by using a binder, water, and a thickening agent, the same material as that used in extrusion molding, was injected into the notch 7, and then the plugging material was dried.

Next, a plugging material was similarly injected through the notches 7 on the back surface side of the surface where the above injection was carried out, and the specific cells were plugged. Then, a paste material made of the same material as the two-layer cell honeycomb structure formed body 6 was applied to the outer peripheral surface 8 of the two-layer cell honeycomb structure formed body 6 by a roller transfer method. A predetermined number of the two-layer cell honeycomb structure molded bodies 6 obtained in the same manner were laminated and pressure-bonded to the outer peripheral surface 8 coated with the paste by the roller transfer method, and bonded. FIG.
It is a perspective view which shows the laminated body of the diesel exhaust gas filter of FIG. In FIG. 6, 6 is a two-layer cell honeycomb structure formed body, 7 is a notch, 8 is an outer peripheral surface, 9 is an exhaust gas inlet side,
Reference numeral 10 denotes an exhaust gas outlet side, which are similar to those in FIG.

The above pressure bonding is 0.02 kg / cm ^{2 to} 0.
A pressure of 06 kg / cm ² was applied. When the pressure for pressure bonding was 0.01 kg / cm ² or less, there was a problem that the laminate was peeled off after firing. Further, when the pressure of the pressure bonding is 0.1 kg / cm ² or more, the cell portion of the two-layer cell honeycomb structure formed body 6 is deformed.
Since the laminated body of the two-layer cell honeycomb structure molded body 6 is arranged in the heat-resistant container of the exhaust manifold portion, the whole area of the laminated uppermost and lowermost notches 7 is plugged, or The paste used for the above-mentioned joining is applied to one sheet of the same quality as the plugging material and joined to the laminated body of the two-layer cell honeycomb structure formed body 6 to prevent gas escape from the portion where the notch 7 is opened. did.

Next, as described above, the layers are laminated in a predetermined shape.
For the pressure-bonded laminated body of FIG. 6, a firing temperature of 1250
Firing was carried out under conditions of 2 ° C. for 2 hours to obtain a silica-based diesel exhaust gas filter.

The diesel exhaust gas filter thus obtained was attached to the exhaust pipe of a 3400 cc diesel engine, and a combustor having an electric heater for ignition installed in a case was attached so that the collected soot could be regenerated by combustion. Engine speed 1200 rpm, torque 20 kg
The engine was operated under the condition of m and the particulate matter such as soot in the exhaust gas discharged from the diesel engine was collected.

In order to evaluate the collection, the smoke value of the soot discharged from the engine, the smoke value after filtering with a filter, and the leakage of the cell portion visually
I checked the traces. The results are shown in (Table 1).

After that, the adhered fine particles of soot and the like were burned and regenerated with an electric heater and the same evaluation as above was carried out, and the same result was obtained.

As is clear from (Table 1), according to the present embodiment, there is no leakage of fine particles such as soot from the plugged cells, and the soot can be collected in a stable manner. Can be obtained. Although not specified in this example, a diesel exhaust gas filter was obtained by applying the same manufacturing method to ceramics such as aluminum titanate, cordierite, and mullite.
The same results as in (Table 1) could be obtained.

As described above, according to this embodiment, the cut 7
Since the plugging agent can be surely injected into each cell that needs to be plugged via, the exhaust gas discharged from the diesel engine or the like can be reliably collected without leaking.
Further, the diesel exhaust gas filter manufactured in this embodiment is of an integral type, has no soot leakage due to vibration during mounting, etc., and has a strength that poses no practical problem. Furthermore, the series of manufacturing steps is performed by cutting 7
Formation, injection of plugging material, application of paste to the two-layer cell honeycomb structure formed body 6, and stacking, pressure bonding, and firing, which are simple operations, so that robot work can be performed and work efficiency can be improved. . Further, since it is possible to determine visually that the plugging material is surely injected, it is possible to make adjustment so that the amount of plugging material filled in each cell does not become uneven.

[0042]

INDUSTRIAL APPLICABILITY As described above, according to the present invention, a molding step of extruding a two-layer cell honeycomb structure molded body and a press-fitting hole at the end of the outer peripheral surface of the molded body on the plugging cell of the two-layer cells. A perforating step or forming step of forming a perforation or a notch, a sealing step of press-fitting or injecting a plugging material from the press-fitting hole or notch to seal a cell for plugging, and a molded body on the outer peripheral surface of the molded body. And an integration step of integrating a predetermined number of two-layer cell honeycomb structure formed bodies by applying a paste of the same material as the above and stacking, crimping and firing to form a paste through the press-fit holes or cuts. A method for manufacturing a diesel exhaust gas filter that can reliably collect exhaust gas discharged from a diesel engine or the like without leaking because a plugging agent can be reliably press-fitted or injected into each cell that needs to be sealed The real It can be.

Further, since the diesel exhaust gas filter is formed integrally, it is possible to realize a method of manufacturing a diesel exhaust gas filter having a strength that does not cause soot leakage even during vibration during mounting and has practically no problem. You can

Further, a series of manufacturing processes is a simple operation of forming a punching hole or a notch, press-fitting or injecting a plugging material, applying a paste to a two-layer cell honeycomb structure molded body, laminating, pressing and firing. Therefore, robot work can be done,
It is possible to realize a method for manufacturing a diesel exhaust gas filter that can improve work efficiency.

Further, since it is possible to visually check or visually confirm that the plugging material is press-fitted or injected, it is possible to adjust the amount of the plugging material filled in each cell so as not to be nonuniform. Therefore, it is possible to realize a method for manufacturing a diesel exhaust gas filter that does not cause uneven combustion.

[Brief description of drawings]

FIG. 1 is a perspective view showing a diesel exhaust gas filter according to an embodiment of the present invention.

FIG. 2 is an enlarged view of part A of FIG.

FIG. 3 is a perspective view showing a laminated body of the diesel exhaust gas filter of FIG.

FIG. 4 is a perspective view showing a diesel exhaust gas filter according to another embodiment of the present invention.

5 is an enlarged view of part B in FIG.

6 is a perspective view showing a laminated body of the diesel exhaust gas filter of FIG.

[Explanation of symbols]

 1, 6 2-layer cell honeycomb structure molded body 2 Press-fit holes 3, 8 Outer peripheral surface 4, 9 Exhaust gas inlet side 5, 10 Exhaust gas outlet side 7 Cut

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shinji Wada 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Koichi Watanabe 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. 72) Inventor St. Matsueda 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Yukinori Ikeda 1006 Kadoma, Kadoma City Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (2)

[Claims] 1. A forming step of extruding a two-layer cell honeycomb structure formed body, and a punching step of forming a press-fitting hole at an end portion of the outer peripheral surface of the formed body on a plugging cell among the two-layer cells. , A sealing step of press-fitting a plugging material through the press-fitting holes to seal the cells to be plugged, and applying a paste-formed material of the same quality as the molded body to the outer peripheral surface of the molded body. A method of manufacturing a diesel exhaust gas filter, comprising an integration step of integrating a predetermined number of the two-layer cell honeycomb structure formed bodies by laminating, pressure bonding and firing. 2. A molding step of extruding a two-layer cell honeycomb structure molded body, and a forming step of forming a notch at an end portion of the outer peripheral surface of the molded body on a plugging cell among the two-layer cells, A sealing step of injecting a plugging material into the notches to seal the cells to be plugged, and applying a paste of a material of the same quality as that of the molded body to the outer peripheral surface of the molded body to stack and
A method of manufacturing a diesel exhaust gas filter, comprising an integration step of integrating a predetermined number of the two-layer cell honeycomb structure formed bodies by pressure bonding and firing.